Corneal degenerations

Abstract

The concept of degeneration means that previously intact tissues are slowly and gradually deteriorating, often to the point where they cannot perform their function properly. As their aetiology is not uniform, their clinical manifestations are also very diverse. The same is true for corneal degenerative conditions. Corneal degeneration may involve deposition of certain substances, thinning of the tissue, vascularization, or a combination of these. What distinguishes them from corneal dystrophies is that they are not hereditary, are often unilateral, and their morphology and localization are much less regular.Corneal degeneration may be peripheral and/or central, superficial and/or deep. It may be primary or secondary according to its origin. They can be grouped in several ways. In origin, they may be (a) age‐related, (b) may develop at the base of other corneal or eye diseases (c) may be the consequence of systemic diseases. (d) may also be caused by drugs and toxins. In many cases the aetiology is obscured. Environmental factors, ultraviolet radiation and oxidative stress are also thought to play a role.Proper diagnosis is essential in choosing effective treatment strategy and thus achieving positive clinical results. When corneal degenerations significantly affect visual acuity, the treatment should aim relieving the primary disease before inducing further changes in the cornea.